Why short bursts of activity are better for you than mammoth cardio sessions.

Mr Craig Ballantyne, inventor of Turbulence Training and frequent contributor to the US edition of Men’s Health magazine, is shaking things up. His provocatively named new book, The Great Cardio Myth, published by Fair Winds Press, claims that the low-intensity, steady-state exercise we’ve been led to believe is vital for longevity and vanity is a scientifically proven waste of time.

If you actively enjoy running or cycling, then by all means fill your Flyknits, and your schedule, with epically long sessions. But if you want to lose weight, improve your health or look better naked as quickly as possible, then plodding along on a treadmill will get you nowhere, fast.

In The Great Cardio Myth, Mr Ballantyne makes a compelling case for high-intensity interval training (HIIT), either by cranking up the treadmill or bike, or by performing circuits of resistance exercises such as press-ups, squats and lunges. Burning fat, building muscle and bolstering your heart in as little as four minutes sounds like the stuff of infomercial fiction, but is backed by research – unlike these remarkably enduring myths about cardio.

Just one minute of HIIT is proven to deliver the same benefits as 45 minutes of conventional aerobic exercise (specifically, three intervals of 20 seconds followed by two minutes of recovery, for a workout totalling 10 minutes, including warm-up and cool-down). Another study reveals that 50 minutes of cardio, five days a week for six months, had no effect on weight loss whatsoever. In fact, it’s common for recreational runners who are training for marathons to put on weight, either because they overestimate what they’ve burned (calorie counters can be wildly inaccurate) or they reward themselves for getting through another interminably tedious session. And any weight you do lose through cardio will include precious muscle, which slows your metabolism and progress. So, you do more and more time-consuming cardio until you get frustrated, injured from the unsustainable volume or simply bored.

This myth originates from studies such as the one that showed cargo-lugging longshoremen lived longer than their office-based colleagues. Somehow these findings were co-opted by the aerobics movement in the 1960s, even though those longshoremen weren’t exactly jogging. While almost any physical activity is better than none, there’s now some suggestion (albeit debated) that “chronic cardio” could be bad for you. The 2015 Copenhagen City Heart Study found that the life-extending benefits of running tail off above 20 miles a week, with negligible differences between the mortality rates of ardent pavement pounders and couch potatoes. Any physical activity can be harmful in excess, including HIIT, but it’s an inconvenient truth that running guru Mr Jim Fixx, PowerBar creator Mr Brian Maxwell and Mr Micah True, the hero of Mr Christopher McDougall’s book Born To Run, all died of heart problems in their fifties.

Unless your desired physique is skinny-fat, that is. Cardio eats lean tissue as greedily as adipose, which is disadvantageous not just for disrobing at the beach, but also for your metabolism (muscle burns more calories when it’s at rest) and health (age-related loss of muscle is a key factor in conditions such as diabetes). Instead of losing arbitrary “weight”, what you really want to do is shed fat while preserving and even building muscle, regardless of whether your goal is to bulk up or merely tone. One glance at the bodies of 100m and 10,000m runners should tell you that sprinting is a better bet than cardio, as are short circuits of resistance exercises such as the ones Mr Ballantyne prescribes. Yes, you’ll have to work hard – an eight or nine out of 10, where 10 is running for your life – but you won’t have to spend your life running.

The Great Cardio Myth (Fair Winds Press) by Mr Craig Ballantyne is available now

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